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Listeriosis risk factors

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [2]; Associate Editor(s)-in-Chief: João André Alves Silva, M.D. [3]

Overview

Risk factors in the development of listeriosis include ingestion of uncooked meats and vegetables, unpasteurized (raw) milk and cheeses, processed (or ready-to-eat) meats, and smoked seafood.[1] Populations at higher risk of developing listeriosis include immunosuppressed patients (e.g. transplant recipients, patients with history of splenectomy, patients receiving immunosuppressive therapy, or patients with advanced diabetes, kidney/ liver disease, or active malignancy), neonates, pregnant women, and elderly patients.[2]

Risk Factors

Ingestion of Contaminated Food

The following foods may be associated with higher risk of developing listeriosis:[1]

  • Uncooked meats and vegetables
  • Unpasteurized (raw) milk and cheeses as well as other foods made from unpasteurized milk
  • Cooked or processed foods, including certain soft cheeses
  • Processed eady-to-eat meats, such as hot dogs and deli meats (contamination may occur after factory cooking but before packaging or even at the deli counter)
  • Smoked seafood
  • Mexican-style cheeses (such as queso fresco)

Shown below is a table summarizing low and high risk cheese types.[3]

Higher Risk Cheese Type Lower Risk Cheese type
Soft cheeses made from unpasteurized (raw) milk, such as:
  • Queso fresco
  • Blue-veined
  • Feta
  • Brie
  • Camembert
  • Soft cheeses that are clearly labeled “made from pasteurized milk”
  • Processed cheeses
  • Cream cheese
  • Mozzarella
  • Hard cheeses

High Risk Populations

The following are considered populations at high risk of developing listeria bacteremia and neurolisteriosis:[4][5]

Pregnant Women

  • Pregnant women are approximately 10-24 times more likely than the general population to develop listeriosis.[6]
  • Approximately 25% to 30% of all Listeria infections occur among pregnant women.

Hispanic Ethnicity

  • Pregnant Hispanic women are approximately 24 times more likely than the general population to develop listeriosis.[6]
  • The association between Hispanic ethnicity and listeriosis is unconfirmed and may be confounded by pregnancy.

Neonates

Elderly Individuals

  • More than half (58%) of all Listeria infections occur among adults older than 65 years of age.
  • Adults 65 years and older are approximately 4 times more likely than the general population to develop listeriosis.[6]

Immnosuppression

References

  1. 1.0 1.1 Listeria (Listeriosis) Sources. CDC.gov accessed on 7/25/2014 [1]
  2. Lorber, B. (1997). “Listeriosis”. Clin Infect Dis. 24 (1): 1–9, quiz 10-1. PMID 8994747. Unknown parameter |month= ignored (help)
  3. “CDC – Prevention – Listeriosis”.
  4. Charlier C, Perrodeau É, Leclercq A, Cazenave B, Pilmis B, Henry B, Lopes A, Maury MM, Moura A, Goffinet F, Dieye HB, Thouvenot P, Ungeheuer MN, Tourdjman M, Goulet V, de Valk H, Lortholary O, Ravaud P, Lecuit M (2017). “Clinical features and prognostic factors of listeriosis: the MONALISA national prospective cohort study”. Lancet Infect Dis. doi:10.1016/S1473-3099(16)30521-7. PMID 28139432.
  5. Goulet V, Hebert M, Hedberg C, Laurent E, Vaillant V, De Valk H, Desenclos JC (2012). “Incidence of listeriosis and related mortality among groups at risk of acquiring listeriosis”. Clin. Infect. Dis. 54 (5): 652–60. doi:10.1093/cid/cir902. PMID 22157172.
  6. 6.0 6.1 6.2 “Vital signs: Listeria illnesses, deaths, and outbreaks–United States, 2009-2011”. MMWR Morb Mortal Wkly Rep. 62 (22): 448–52. 2013. PMID 23739339. Unknown parameter |month= ignored (help)

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